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#867513 12/29/21 7:59 am
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Hello All,
I have two T160s, both have a false neutral 2nd to 3rd. One annoying and the other really bad.
Any ideas?

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The following is copied from a post on the TOL forum by triples expert Phil Pick.

"Thinking about overall suggestions for an often missed 2nd to 3rd: I can only come up with two at the moment, and both are a little wierd! If the top-hat bush in layshaft 2nd has come loose, and moved out of position then layshaft 2nd will be sitting too far to the right on the shaft. Layshaft 3rd is dog engaged within this gear when 2nd is selected. If, on the change up to 2nd layshaft 3rd has engaged with the layshaft 2nd dogs, but the incorrect positioning of layshaft 2nd has not released all the camplate to selector fork load on layshaft 3rd, the camplate (and therefore the footchange mechanism) will not have returned fully to the 'rest' position. When the change to 3rd is attempted the camplate will not be fully correctly driven, and 3rd may be 'missed. Secondly, if the mainshaft inner bearing is loose (in an axial sense, not properly retained by the circlip) then the mainshaft may be sitting too far to the right. This means that mainshaft 4th (this engages dogs with mainshaft 3rd as 3rd is selected) may not be making sufficient engagement to allow the undercut on the dogs to 'hold' the gear in place."
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Since the triple's gearbox is so similar to the twin this is what I went through recently to correct the exact same thing on a late 650 5 speed gearbox.
Neutral down to 1st perfect, then up to 2nd was also perfect. 2nd up to 3rd was a total crapshoot, 3 to 4 a bit better. Ditto for 4th to 5th. All downshifts were fine.
I could hand shift it on the stand (not running) and feel that the 2-3 was undershifting. I measured the swing in degrees of the quadrant and found a distinct difference in the upshift vs downshift rotation . I filed the quadrant upshift swing stop to match the downshift swing, installed new quadrant springs and it now shifts perfectly. There was absolutely nothing wrong inside the gearbox, all the issues were in the shifter cover.
Best wishes for an equally simple repair.

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Thanks Bob, I'll check that. All my missed 3-2 shifts are in the downshift direction


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." I filed the quadrant upshift swing stop to match the downshift swing, installed new quadrant springs and it now shifts perfectly."
Bob did a great job and got a great result (he lives near me and we are good friends).
IME in most cases the simple replacement of the curved quadrant springs restores gear shifting to slickness.
A lot of those springs are now around 50 years and over that time tend to take a "set".
They are also subject to weakening by wire diameter reduction due to rusting in the outer cover.
I always smear grease on all the springs and operating surfaces in the outer cover.
HTH

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Originally Posted by Tridentman
." I filed the quadrant upshift swing stop to match the downshift swing, installed new quadrant springs and it now shifts perfectly."
Bob did a great job and got a great result (he lives near me and we are good friends).
IME in most cases the simple replacement of the curved quadrant springs restores gear shifting to slickness.
A lot of those springs are now around 50 years and over that time tend to take a "set".
They are also subject to weakening by wire diameter reduction due to rusting in the outer cover.
I always smear grease on all the springs and operating surfaces in the outer cover.
HTH
Tridentman isn't joking, stuff does happen over time and the outer cover is a veritable rust box.
This is a 5T 1957 I just opened, it's been sitting since 1999. Grease in here is good advice!

SR

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Thanks everybody.

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SR...that is some rusty shifter cover! Those detent plungers sure took a beating.😥

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Originally Posted by BobV07662
SR...that is some rusty shifter cover! Those detent plungers sure took a beating.😥
I should have taken a picture of the plunger plate, all rust! Amazingly the rest of the box was fine, apart from wear in the layshaft journals and bearings. Preserving the gear shift mechanism with grease or some other sticky lubricants helps, and avoiding bathroom type sealants, as many of these give off acidic vapors when they cure.

SR


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